Field of the Invention
The present invention relates to an unfinished ferrule assembly and a fiber optic ferrule device for a fiber optic connector.
Description of the Related Art
FIG. 1a is an illustrative view of a single-fiber ferrule assembly (ferrule device) 10 of a fiber optic connector the in prior art; and FIG. 1b is a cross section view of the single-fiber ferrule assembly 10 shown in FIG. 1a. 
As shown in FIG. 1a and FIG. 1b, in the prior art, during manufacturing the single-fiber optic connector, the ferrule assembly 10 comprising a ferrule 12 and a rear seat 11 connected to a rear end of the ferrule 12 is usually used. The rear seat 11 may be a plastic member formed on the rear end of the ferrule 12 by molding, or may be a metal member fixed on the rear end of the ferrule 12 by crimping.
As shown in FIG. 1a and FIG. 1b, a hollow chamber 14, for receiving an adhesive, is formed in the rear seat 11. An axial front port of the hollow chamber 14 is coaxial and communicated with a fiber bore 15 in the ferrule 12. During manufacturing the fiber optic connector, an enough adhesive is firstly injected into the hollow chamber 14 through an axial rear port (adhesive injection port) 13 by means of an adhesive injection needle (not shown), then a bared and cleaned fiber of the optical cable is inserted through the hollow chamber 14 and the fiber bore 15, fully filled with adhesive, of the ferrule assembly 10, then the adhesive is cured to fix the fiber in the fiber bore 15 of the ferrule assembly 10, then the ferrule assembly 10 is processed by a series of procedures, such as, grinding, polishing, testing, assembling, etc., and finally, a fiber optic ferrule device (finished ferrule assembly) is obtained.
The ferrule assembly 10 shown in FIGS. 1a and 1b in the prior art is configured to be adapted to fill the adhesive into the ferrule assembly before inserting the fiber into the ferrule assembly. However, in some special conditions, it is necessary to insert the fiber into the ferrule assembly before filling the adhesive into the ferrule assembly. Thereby, the ferrule assembly 10 shown in FIGS. 1a and 1b in the prior art is not satisfied with such requirement. In the prior art, if the fiber is inserted into the ferrule assembly 10 through the axial rear port 13 before the adhesive is injected into the ferrule assembly 10 through the axial rear port 13 of the ferrule assembly 10, then, during filling the adhesive into the ferrule assembly 10 by means of an adhesive injection needle inserted through the axial rear port 13 and entering into the hollow chamber 14, it is possible that the adhesive injection needle touches and damages the fiber that has been inserted into the ferrule assembly 10. In order to avoid touching the fiber inserted into the ferrule assembly 10, sometimes, it needs to reduce the depth of the adhesive injection needle entering into the ferrule assembly 10, and it may cause a problem that the adhesive injection needle does not reach the hollow chamber 14, and the adhesive cannot be injected to a proper location in the ferrule assembly. In this case, it is difficult for the adhesive to flow over the whole fiber bore 15 in the ferrule assembly 10.
In the prior art, the adhesive must be filled into the hollow chamber 14 of the rear seat 11 through the rear end port 13 before the fiber is inserted into the ferrule assembly 10 through the rear end port 13. As a result, during inserting the fiber into the ferrule assembly fully filled with the adhesive, the adhesive adheres to the fiber. It increases the resistance of inserting the fiber and may cause the fiber broken. Furthermore, the adhesive adhered on the front end surface of the fiber decreases the optical performance of the fiber. Therefore, it is necessary to clean the adhesive from the front end surface of the fiber.